Use of 要...(了) to indicate future

Question

This is a question about the use of 要 yào as a verb to indicate immediate future ('going to') and its common complementation by 了 le.

要 is a confusing word for learners because of its various meanings. It is usually introduced in beginners' textbooks with the meaning 'to want', which is fine when used as main verb with a noun phrase, as in 我要一杯茶, 'I want a cup of tea'. In this case, I think it is synonymous with the two-character version 想要 xiǎngyào, so we can equally say 我想要一杯茶, with no major change of meaning (maybe just a softer tone, 'I would like' as opposed to a blunt 'I want', in the longer form).

But when used as an auxiliary verb, followed by another verb, 要 can also indicate a future action, a bit like 會 huì or the formal 將 jiāng, but more immediate (I think the subtle difference is similar to 'be going to' v. 'will' in English). This is clear in sentences where there is no possible interpretation in terms of wishing to do something, as in 要下雨了, 'it's going to rain'. In this use, it is often complemented by a final 了.

But where do we draw the line between 'wanting to do something' and 'being going to do something'? I'm aware that these meanings can overlap to a certain extent. If I say 'I'm gonna play football with my friends this evening', I'm both stating an intention and something that I want to do. But it's also possible to be about to do something reluctantly or, conversely, to want to do something that is, however, not possible.

Following on the 'I want a cup of tea' example, consider the following two sentences:

我要喝一杯茶。(1a)
我要喝一杯茶了。(1b)

Should we understand these sentences as 'I want to drink a cup of tea' and 'I now want to drink a cup of tea' (assuming a change-of-state 了 in 1b)? Or simply as 'I'm gonna drink a cup of tea'? Does the use of a final 了affect whether 'wanting' or 'going to' is implied?

Now let's suppose I want to say 'I'm gonna pay a lot of taxes this year'. This is clearly not something I want to do. Are the following translations fine?

今年我要付很多稅。(2a)
今年我要付很多稅了。(2b)

Does the final 了 in 2b change the meaning? A final question: would the two-character version 將要 jiāngyào also work here?

今年我將要付很多稅。(2c)
今年我將要付很多稅了。(2d)

Answer 1

要 - "want/must/need/will do", usually speaking in a definite/strict/firm tone for something non-negotiable.

• 我要喝這杯茶. - I want to drink this cup of tea. (Don't compete with me.)

• 今年我要付很多稅. - (The fact is,) I need to/must pay a lot of taxes this year.

• 今天傍晚我要跟朋友去踢足球 - I need to go play soccer with friends this evening (, so I can't watch the movie with you)

想要 - "wanting to", usually used when requesting something desirable, or indicating a wish on something you intended to do, but not strongly/firmly affirmative.

• 我想要喝這杯茶. - I am wanting to drink this cup of tea (because I am thirsty).

• 今天傍晚我想要跟朋友去踢足球 - I am wanting to play succor with friends this evening. (It is your wish but you may not for other reasons.)

Note, you can't say "今年我想要付很多稅.", because paying more tax is simply not desirable. Instead, you can say "今年我想我要多付很多稅." - I think/guess I need to pay much more tax this year.

(将)要...了 - "going to", usually expressing expectation, sometimes with a slight sense of threatening, complaining, or relief.

• (将)要下雨了. - It is going to rain soon (as I expected/predicted).

• 我(将)要喝這杯茶了. - (Look,) I am going to drink this cup of tea now.

• 今年我(将)要付很多稅了. - (So unlucky,) I am going to pay a lot of taxes this year.

• 今天傍晚我(将)要跟朋友去踢足球了. (Finally,) I am going to play soccer with friends this evening.

Answer 2

It's because of omissions. "我要喝一杯茶" can be short for both "我想要喝一杯茶" and "我将要喝一杯茶". When we say "我要喝一杯茶" it can mean "I want a cup of tea" or "I'm gonna drink a cup of tea". In colloquial speach, people often omit "想" and "将". (PS."我要喝一杯茶" also means "I need a cup of tea 我需要喝一杯茶") So when we talk about "我要喝一杯茶" we actually mean "我(想/将/需/...)要喝一杯茶". The meaning depends on the context. "了" is not the key word in these sentences.